In this paper, we first report the preparation of poly (urea–formaldehyde) (UF) microcapsules filled with liquid polysulfide by one-step in situ polymerization. For obtaining the optimal pr...

Preparation and mechanical properties of poly (urea–formaldehyde) microcapsules containing liquid polysulfide

Microcapsules containing initiator for anaerobic adhesive by in situ polymerization in which urea-formaldehyde resin was used as the wall material and benzoyl peroxide was used as the core material.The influences of different kinds of emulsifiers such as sodium dodecylben-zenesulfonate,tween-80,gum arabic and styrene-maleic anhydride and other process conditions on the preparation of microcapsulation were investigated,and IR,TG and SEM were used to analyse the microcapsules.When the microencapsulation was conducted in a system modified by multiple emulsifiers,i.e.,the mixture of styrene-maleic anhydride copolymer and gum arabic,the end point pH value was at around 1.5,the reaction temperature was 70 ℃,the reaction time was 4 h,and the agitation rate was of 1 000 r/min,the microcapsules were dispersed moderately in size,with good shape and appearance,and the diameter was about 100 μm.The performance of the precoating type adhesive made up of the microcapsules prepared in this article could match that of the ones made by Loctite Company in America.

Bai Ruo

Papers

Preparation of Microcapsules Containing Initiator for Anaerobic Adhesive by in situ polymerization